# e85Cal vs Flash Tree

The clearest difference is rating: e85Cal at 4.7 against Flash Tree's 4.0. e85Cal also leads on in-app purchases (none vs 1) and ratings volume (35 vs 4). Flash Tree's advantage is update cadence (every 10 days vs every 4 months) and review sentiment (100% vs 83%). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Flash Tree sells 1 in-app purchase, starting at $9.99 per month. e85Cal asks for nothing beyond the download.

e85Cal holds the better App Store score, 4.7 against 4.0. That said, the two scores are not equally well evidenced: e85Cal has 35 ratings behind it against 4, so its average is the more settled of the two. Written reviews complicate that: 83% of e85Cal's written reviews are positive against 100% of Flash Tree's, so the app with the better star average is not the one people write more warmly about.

e85Cal ships an update every 4 months, Flash Tree every 10 days. Both last shipped on September 26, 2026.

## The numbers

| Metric | e85Cal | Flash Tree |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (35 ratings)](https://appshunter.io/ios/app/e85cal/id1470313135/reviews)** | [4.0 (4 ratings)](https://appshunter.io/ios/app/flash-tree/id1591487632/reviews) |
| Number of ratings | **35** | 4 |
| Positive reviews | 83.3% of reviews | **100.0% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 10 days** |
| Monetization | **Free** | Freemium |
| Size | 15 MB | 30 MB |
| Requires iOS | 12.1 | **11.0** |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Michael Joe](https://appshunter.io/developer/1132486512) | [BUILDMYPAGE, LLC](https://appshunter.io/developer/1550205663) |

## What reviewers say

### e85Cal

[App page](https://appshunter.io/ios/app/e85cal/id1470313135)

This app assists users in calculating the precise amounts of standard and ethanol gasoline needed to achieve a desired ethanol percentage in their fuel mix. It simplifies the process by taking into account tank size, current fuel level, and the ethanol content of available fuel types.

**Highlights:** Calculate ethanol percentage goal, Enter gas tank size, Input standard pump gas ethanol %, Input ethanol pump gas ethanol %, Set target ethanol % mix, Enter current fuel level %

**Features:** macOS Compatibility

**In-app purchases:** none


### Flash Tree

[App page](https://appshunter.io/ios/app/flash-tree/id1591487632)

Synchronize countdown timers across multiple devices for group races or events. Start races instantly without needing external assistance. Ideal for competitive activities where precise timing is crucial.

**Highlights:** Synced countdown timers, Group race functionality, Start races instantly, Multi-device synchronization, Customizable countdowns

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Flash Tree Subscription | $9.99 | per month |


## Frequently asked questions

### Is e85Cal free?

e85Cal is free to download, with no in-app purchases.

### Is Flash Tree free?

Flash Tree is free to download, with in-app purchases available.

### Which has better reviews, e85Cal or Flash Tree?

e85Cal is rated higher. e85Cal averages 4.7 out of 5 from 35 ratings, while Flash Tree averages 4.0 from 4 ratings.

### Do e85Cal or Flash Tree have ads?

Neither e85Cal nor Flash Tree shows ads.

### Which is updated more often, e85Cal or Flash Tree?

e85Cal ships an update every 4 months, and Flash Tree every 10 days. Most recently, e85Cal was updated on September 26, 2026 and Flash Tree on September 26, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*